基于HYDRUS-1D模型的荒漠绿洲水盐运移模拟与评估  

Simulation and evaluation of soil water and salt transport in desert oases of Hetao Irrigation District using HYDRUS-1D model

作　　者：王国帅 史海滨[1,2] 李仙岳 闫建文[1,2] 苗庆丰 陈宁[1,2] 王维刚 Wang Guoshuai;Shi Haibin;Li Xianyue;Yan Jianwen;Miao Qingfeng;Chen Ning;Wang Weigang(College of Water Conservancy and Civil Engineering,Inner Mongolia Agricultural University,Hohhot 010018,China;High Efficiency Water-saving Technology and Equipment and Soil Water Environment Engineering Research Center of Inner Mongolia Autonomous Region,Hohhot 010018,China)

机构地区：[1]内蒙古农业大学水利与土木建筑工程学院,呼和浩特010018 [2]高效节水技术装备与水土环境效应内蒙古自治区工程研究中心,呼和浩特010018

出　　处：《农业工程学报》2021年第8期87-98,共12页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金资助项目(51539005,51769024)。

摘　　要：针对河套灌区引水量逐年减少、荒漠绿洲农业生态环境恶化等问题,该研究以沙丘-荒地-海子系统为研究对象,通过2a定点观测,利用HYDRUS-1D模型对沙丘、沙丘-荒地交界和荒地进行了不同时期水盐动态模拟,揭示了荒漠绿洲水盐运移特征,评价了荒漠绿洲农业生态状况。结果表明:1)沙丘、沙丘-荒地交界和荒地土壤水分和盐分率定与验证精度平均相对误差分别为-1.30%~1.52%和-0.43%~5.71%,均方根误差为0.01~0.03 cm^(3)/cm^(3)和0.06~0.23dS/m,决定系数为0.82~0.93和0.76~0.82,回归系数为0.98~1.01和0.98~1.03,模拟精度较高;2)在生育期,沙丘、沙丘-荒地交界和荒地1 m土体各层水分呈现下降趋势,土壤处于亏水状态,荒地腾发量是沙丘的2倍,沙丘-荒地交界的介于二者之间,荒地地下水补给量为沙丘的3~5倍;秋浇后,沙丘水分补给较少,仍亏水67~103 mm,沙丘-荒地交界和荒地水分补给较多,可以维持土壤水分平衡;3)沙丘、沙丘-荒地交界和荒地全年处于略积盐状态,积盐率分别为47%~59%和3%~6%,荒地在秋浇后处于轻微脱盐状态,脱盐率为0.7%~5.0%。研究发现,降雨对维持荒漠绿洲农业生态平衡的作用较小,秋浇灌溉对改善灌区荒漠绿洲农业生态发挥关键作用。研究结果可为河套灌区荒漠绿洲农业生态治理提供参考。Great changes have occurred in the agricultural ecology,due mainly to the ever-decreasing water diversion from the Yellow River,particularly for the desert oases in the Hetao Irrigation District of China.Taking a sand dune-wasteland-lake system as the research object,this study aims to simulate and evaluate the soil water and salt transport during the growth period in the desert oases after autumn irrigation using HYDRUS 1D model.Two-year experimental data was selected to simulate the water and salt dynamics of the sand dune,wasteland,and the junction of sand dune-wasteland.As such,the characteristics of water and salt transport were revealed to evaluate the agro-ecological situation in desert oases.The results showed that a highly accurate assessment was achieved in the soil water content,where the mean relative error(MRE)was-1.30%-1.52%in calibration and validation,the root mean square error(RMSE)was 0.01-0.03cm^(3)/cm^(3),the coefficient of determination(R2)was 0.82-0.93,and the regression coefficient(b)was 0.98-1.01.A simulated accuracy was also acceptable in the soil salt content,where the MRE was-0.43%-5.71%,the RMSE was 0.06-0.23 dS/m,the coefficient of determination(R2)was 0.76-0.82,and the regression coefficient(b)was 0.98-1.03.Specifically,the water content at the soil layer of 20,40,60,80,and 100 cm in the sand dune decreased by 25%,32%,34%,37%,and 35%,respectively.The storage of soil water also decreased by 102-114mm.The soil water loss of sand dune still remained 67-103mm,where there was less recharged flow from groundwater.It inferred that the sand dune was in a state of water deficiency during the whole year.The water content at the soil layers of 60-100cm in the sand dune-wasteland junction decreased by 18%-22%,whereas,the soil water storage increased by 61mm after autumn irrigation.The water content at the soil layers of 20,40,60,80,and 100cm in the wasteland decreased by 16%,17%,27%,42%,and 34%,respectively,while the soil water storage decreased by 160-228 mm,but the soil water storage increased

关 键 词：土壤 盐分 水盐运移 秋浇 HYDRUS-1D 荒漠绿洲 河套灌区 

分 类 号：S274[农业科学—农业水土工程]